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    <title>invr</title>
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    <center>Scilab Function</center>
    <div align="right">Last update : April 1993</div>
    <p>
      <b>invr</b> -  inversion of (rational) matrix</p>
    <h3>
      <font color="blue">Calling Sequence</font>
    </h3>
    <dl>
      <dd>
        <tt>F = invr(H)  </tt>
      </dd>
    </dl>
    <h3>
      <font color="blue">Parameters</font>
    </h3>
    <ul>
      <li>
        <tt>
          <b>H</b>
        </tt>: polynomial or rational matrix</li>
      <li>
        <tt>
          <b>F</b>
        </tt>: polynomial or rational matrix</li>
    </ul>
    <h3>
      <font color="blue">Description</font>
    </h3>
    <p>
    If <tt>
        <b>H</b>
      </tt> is a polynomial or rational function matrix, <tt>
        <b>invr</b>
      </tt>
    computes <tt>
        <b>H^(-1)</b>
      </tt> using Leverrier's algorithm (see function code)</p>
    <h3>
      <font color="blue">Examples</font>
    </h3>
    <pre>

s=poly(0,'s')
H=[s,s*s+2;1-s,1+s]; invr(H)
[Num,den]=coffg(H);Num/den
H=[1/s,(s+1);1/(s+2),(s+3)/s];invr(H)
 
  </pre>
    <h3>
      <font color="blue">See Also</font>
    </h3>
    <p>
      <a href="../linear/glever.htm">
        <tt>
          <b>glever</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="coffg.htm">
        <tt>
          <b>coffg</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="../linear/inv.htm">
        <tt>
          <b>inv</b>
        </tt>
      </a>,&nbsp;&nbsp;</p>
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